Also found at Tell ed-Der were letters to another official, Ikunpisha, which were from kings Sumu-abum and Sumu-la-El of Babylon.
The language spoken around Rosita and Bonanza in the north-eastern part of the RAAN, and today known as 'Mayangna', is in fact two closely related dialects, Twahka and Panamahka, while the people of Karawala in the RAAS, who were also formerly regarded as 'Sumu', speak a closely related sister-language called Ulwa.